SANTA MARIA, California (CNN) -- Actor Macaulay Culkin took the stand Wednesday to defend his friend, saying Michael Jackson "never" sexually molested him or touched him in an improper or offensive way when he was a boy.

Calling the allegations against Jackson "absolutely ridiculous," Culkin told jurors that staying over at Jackson's Neverland Ranch was "good old fun."

Culkin acknowledged sleeping in Jackson's bed a dozen or more times between the ages of 9 and 14, but insisted nothing of a sexual nature happened between the two. "I've fallen asleep in the same bed with him," Culkin said. "I'd just flop down."

He testified his parents trusted Jackson, were aware that he and Jackson sometimes shared a bed and that Culkin's father would even come into the pop star's bedroom to wake up his son.

"They never really saw it as an issue," Culkin said. "I knew they knew I was in the room."

Culkin's testimony was part of a bid by the defense to dispute earlier prosecution testimony that Jackson had a habit of grooming young boys for seduction. Culkin is one of the males prosecutors allege was singled out by the pop star while they were boys.

Culkin said that during his visits to Neverland, he was almost always accompanied by "some kind of combination" of his parents, brothers and sisters who also were friends with the pop star. He said that Jackson had an "open door" policy, never locked his bedroom door, and that when he slept with Jackson, Culkin said, he wore jeans, socks and a T-shirt.

The 24-year-old star disputed earlier testimony from two former Neverland employees who said they saw Jackson behaving inappropriately with him in the early 1990s, when he was a visitor at the ranch. Culkin said he was troubled that those allegations were "out there, and people were thinking about it."

He said he first learned of the testimony when a friend called to tell him, "You better check out CNN. They're saying something about you."

"I couldn't believe it," he said.

"I've never seen him do anything improper with anybody," Culkin told jurors.

Culkin during cross-examination

During cross-examination, prosecutor Ron Zonen pressed Culkin on whether Jackson might have molested him when he was asleep -- a scenario similar to the accusations in the current indictment against Jackson.

"As far as I know, he's never molested me," Culkin said. "I find that unlikely. I think I'd realize if something like that would be happening."

A former maid, Adrian McManus, also testified she once saw Jackson put his hand on Culkin's leg and buttocks and kiss him on the cheek while they were sitting together in Neverland's library.

A grand jury indicted Jackson last year on charges of molesting a then-13-year-old boy, giving him alcohol and conspiring to hold him and his family captive in 2003. Jackson pleaded not guilty to the charges.

'We had this understanding'

Culkin, who was born in 1980, became friends with Jackson in the early 1990s, after he rocketed to fame in "Home Alone" and other movies. He told jurors that the two of them bonded because they were part of a "unique group" of people forced to deal with the complications of fame at an early age.

"We had a really close relationship," Culkin said. "We had this understanding of one another."

He told jurors Wednesday that Jackson had a childlike quality, playing arcade games with the children who were staying with him at the ranch.

"Although, he wasn't as good as us," Culkin said, as he looked in Jackson's direction.

Pressed by Zonen about the propriety of a 35-year-old man having such a close friendship with a 10- or 11-year-old boy, he replied, "I wasn't friends with a lot of 35-year-old men who understood me."